Process of manufacturing hydroquinone



Patented June 2, 1925' 311mm: mania, or nnnnm-mmxwrrz, GERMANY, 'assrerron 'ro cnnmrscan FA- BBIK AUF .AO'IIEN (VOEM. E. SCHERING), OF BERLIN, GEEK o PROCESS OF MANUFACTURING HYDBOQUINONE.

Ho Drawing.

To all whom it may concern Be it known that I, HERMANN Emnn, citizen of Germany, residing at. Berlin-Lenkwitz, Germany, have invented ,a new and useful Im rovement in Processes for Mann facturing ydr uinone, of which the following is a speci cation.

The quinhydrone resulting during the reduction of quinone to hydroquinone by means of the methods used hitherto proves to be very resistant against the substances used for reduction in, those methods when the qu' ydrone is not dissolved in water but only suspended.

I now have found out that quinhydrone even when not, dissolved can be reduced to hydroquinone very quickly and with an exoellent output when being heated with iron and water.

EwmnpZe.

To a boiling and thoroughly agitated mixture of 2.2 parts of iron and 60 parts of water 5.5 parts of quinhydrone are added,

taking care that no quinone vapors escape.

From'this mixture which is to be boiled another hour the hydroquinone is isolated as usual. v

This process can be taken advantage of in the reduction of quinone to hydr uinone by reducing the quinoneto about qumhydrone in the usual we and heating the reaction mixture containing quinhydrone with iron an d water. s Example.

EiThe sulphuric quinone solution obtained i by the ondation of 9.3 parts of. anih'n is Application filed August a, 1921.- Serial Ira-49am.

mixed with 2.8 parts of iron powder or added to a well agitated boiling mixture of 2.2 parts of iron powder and parts of water; Thehydroquinone'is isolated in the usual way,

I claim as my invention: 7 1. The process of making hydroquinone which consists in heating. a quinhydrone with iron and water. Q

2. The process of making hydroquinone which consists in adding a quinhydrone to a boilingmixture of iron and water, taking care that no quinone vapors escape, heating the mixture further and lsolating the hydroquinone. 1

3. The process of making hydroquinone, which consists in heating with iron and water the reaction mixture, resulting from the usual way.

4. The process of reducing quinone to about quinhydrone making h droquiho e,

which consists in gradually a ding the reaction mixture, resultin from reducing quinone toabout quinhydrone in the usual way, to a boiling mixture of iron and water and isolating the hydro uinone. I

In testimony whereof have hereunto set my signature in the presence of two subscribing witn 1 rI R ANN EMDE. 

